Absolutely. No argument here Dave
I think though that you are getting confused with Psychological disoprders and the SOul. The Soul is not affected by the brain. The Mind is in fact a computer, thats all it is. It can get confused and lose memories. But Soul memories are not stored in the brain, they are in the soul. Your personality is partly down to genetics, partly to social conditioning and partly to the soul in my opinion.
Like those Killers who where abused as children, brought up in a rough neighbourhood etc...etc... except they have a pet cat whom they love...how can you find any correlation in that behaviour? Which is why I think the Mind personality and the Soul personality are very different indeed.
And as such Bi-Polar, ADHD, Schizophrenia etc...etc...have nothing to do with the soul at all